Flameproof switchboard



Sept. 19, 1939. l.. R. FIEDLER 2,173,101

FLAMEPRooF swITcHBoARD Filed sept. '7, 1955 2 #neem-sheet 2 Lionel "Nv' alle,

usw-JM- ATTORNEY Patented Sept. 19, 1939 UNITED STATES PATENT FFICE 1 Claim.

(Granted under the act o! March 3, 1883, as amended April 30, 1928; 370 O. G. 757) This invention relates to electrical switchboards and it has particular relation to switch and terminal boards of the multiple unit type.

One of the objects of the present invention is i the provision of a switchboard of the character described in which all oi the instruments and electrical connections of each unit are normally completely inclosed so as to minimize nre hazard and to prevent flames which may develop in one unit from spreading to another, the construction and arrangement being such that each unit may quickly and easily be withdrawn from the face of the panel in order to test and adjust the various equipment and connections without disconnecting the leads or interrupting the service.

Another object of the invention is the provision of a switchboard having two terminal boards, one for the bus wiring and one for the lead-in wires, the latter being removable to provide ac- IU cess to the several connections and terminal posts, the two board construction materially increasing the number of possible connections. Still another object of the invention is the provision of a switchboard that can completely be 25 wired and tested prior to shipment from the factory.

A further object oi the invention is the provision oi a switchboard having an inclosure at the bottom into which the incoming cables, which are 80 not name-proof, extend and in which they terminate, thus insuring that any nre originating in any one of the several compartments of the switchboard cannot damage these cables or travel along them to other inflammable material.

35 With these and other objects in view, as well as other advantages which may be incident to the use of the improvements, the invention consists of the parts and combinations thereof hereinaiter set forth and claimed, with the under- 0 standing that the several necessary elements constituting the same may be varied in proportion and arrangement without departing from the nature and scope of the invention as dened in the appended claim.

In order to make the invention more clearly understood there are shown in the accompanying drawings, means for carrying the invention into practical eect, without limiting the improvements in their useful application to the particu- 50 lar construction, which. for purpose of explanation, have been made the subject of illustration.

In the accompanying drawings:

Fig.' l is a side View of a switchboard constructed in accordance with the invention but with the 55 side wall thereof removed;

Fig. 2 is a fragmentary side elevational view of the rear portion of the switchboard with the back hinged terminal panel swung down; and

Fig. 3 is a side elevational view of a multiple unit switchboard embodying the invention. 5

Referring to the drawings, a single stack of multiple unit switches constructed in accordance with the invention is shown as comprising forwardvertical frame members or angle bars I0 connected by transverse bars Il also of angle construction. This frame supports a plurality of compartments I2, each having a top I3, a bottom I4, and side walls I5. The front, however.' is open and is formed with top and bottom anges I6 which are suitably secured to the vertical and l transverse bars I0 and II. The rear or each compartment is closed by a bus or terminal board Il of insulating material which is suitably fastened to inturned flanges I8 provided on the top and bottom of the compartment and which carries a plurality of bus terminal posts I9.

At the rear of the bus terminal board il and spaced therefrom is an inlet terminal board 2B also of insulating material having a plurality of posts 2| mounted thereon. This terminal board 25 is hinged at its lower edge as at 22 to a horizontal plate or shelf 23, secured at its forward edge to the front terminal board I1. The upper edge of the terminal board 20 is removably secured by means of wing bolts to the outer ends of rods 30 which extend rearwardly from the terminal board I1 to which they are secured. Access may readily be obtained to the several terminal posts I5 and 2| in order to make any desiredconnections, by merely unscrewing the bolts 24 and swinging the 85 terminal board 20 downwardly to the horizontal position shown in Fig. 2.

Slidably mounted in each of the compartments I2 is a receptacle 26 having a metallic top and bottom 21 and 28 respectively and a rear wall 25, 4o but open at its sides to provide access to its interior when drawn out, as shown at the lower portion of Fig. 1. The front of the receptacle 25 is, however, closed by a main switch panel which is bolted to inturned flanges Si provided on the top and bottom of the receptacle.

The receptacle 26 is adapted to house certain electrical instruments or equipment which may, for example, include a rotary switch 32 mounted on the front panel 30, a fuse 33 and a trouble 50 light 34 which are carried by a bracketv 35 secured to the top 21, a transformer 36 and relay 31 also carried by the top 2l. Wires 38 from a cable 39 supply electrical energy to the several instruments referred to. The cable 39 passes 55 through a small'opening in the rear wall 29 and thence through the bus terminal board I1 where the wires 3B are connected with the proper binding posts I9 and 2I. It will be noted from an inspection of Fig. 1 of the drawings, that the cable 39 is oi.' such length as to permit the receptacle 28 to be withdrawn for inspection purposes, the slack in the cable doubling upon itself and being contained within a space between the rear wall 29 of the receptacle and the bus terminal board I1 when the receptacle is slid back into its normal position within the compartment I2.

The receptacle 26 is normally secured in its closed position by bolts 4I which pass through the front panel 30 for threaded engagement with the angle bars I I. Also, the front panel 30 may be provided with a small swinging door 42 through which the interior of the receptacle may be observed and through which the fuse 33 and trouble light 34 are accessible.

Electric current is supplied to the several wires 38 of the diiferent sections or units of the assembly through wires 43 which are connected with the various terminal posts 2I exteriorly of the rear terminal board 20 and which issue from a main trunk line or cable 44. 'I'his cable 44 is provided with a name-proof covering and extends downwardly, as shown in Fig. 3, and into .a closed compartment 45 located at the bottom of the stack of switch units hereinabove described, where the various wires 43 are connected with a series of terminal posts 46 carried by a terminal board 41. Wires 48 issuing from incoming cables 49 which are not provided with flame-proof coverings are lnclosed within a closed compartment 50 located at the rear of the compartment 45 and are connected with the several terminal posts 46.

Thus, should a re develop in any one of the switch unit inclosures it cannot pass to other switch inclosures or to the incoming cables. In

the above-described switchboard the parts are all accessible and new connections may be made and old connections altered or repaired with a minimum of time and effort.

Various modications and changes in proportions and arrangement of the parts may be made by those skilled in the art without departing from the spirit and scope oi the invention as dei'lned in the appended claim.

The invention described herein may be manu- Iactured by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is:

A switchboard of the character described comprising a closed compartment, an open sided receptacle mounted for sliding movement between positions within and without said compartment and adapted tohouse a plurality of electrical instruments and associated wiring, an instrument panel carried by the outer exposed end of said receptacle, a iirst terminal board forming the rear end of said compartment, nameproof flexible conductors connecting the instruments within said receptacle with the terminals on said first terminal board and of such length as to permit of the free movement of said receptacle, an open sided compartment located to the rear of said closed compartment, a second terminal board forming the rear end oi' said open sided compartment, non-flameproof conductors located in said open sided compartment for connecting the terminals on said rst and second terminal boards, said second terminal board being mounted to swing outwardly to provide access to the terminals and conductors in said open sided compartment.

LIONEL R. FIEDLER. 

